British Dictionary definitions for unit (1 of 2)

noun

any group or individual, esp when regarded as a basic element of a larger whole

a mechanical part or integrated assembly of parts that performs a subsidiary functiona filter unit

a complete system, apparatus, or establishment that performs a specific functiona production unit

a subdivision of a larger military formation

Also called: unit of measurementA standard amount of a physical quantity, such as length, mass, energy, etc, specified multiples of which are used to express magnitudes of that physical quantitythe second is a unit of time

the amount of a drug, vaccine, etc, needed to produce a particular effect

a standard measure used in calculating alcohol intake and its effect

maths

(usually plural)the first position in a place-value counting system, representing a single-digit numberin the decimal system the number 27 has 7 units and 2 tens